在字符串中的每个逗号后添加双引号

Question

我有一个类似于下面的字符串-并希望在字符串中的每个逗号后添加双引号。

我试图用“，\”“替换，但是没有用。

//orginal strign
char *mystring = "test,blabla,blabla,blabla";

//want to convert this format, after adding double quote
char *newstring = " test,\"blabla,\"blabbla,\"blabla";

如何用C编程语言在字符串中的每个逗号后面加上双引号？

Answer 1

如果我很了解您想要这样的话：

#include <stdio.h>
#include <stdlib.h>

int main()
{
  const char *mystring = "test,blabla,blabla,blabla";
  int n = 0;
  const char * p1;

  /* compute result length */
  for (p1 = mystring; *p1; ++p1)
    n += (*p1 == ',') ? 2 : 1;

  /* make result string */
  char * r = malloc(n + 1);
  char * p2 = r;

  for (p1 = mystring; *p1; ++p1) {
    if ((*p2++ = *p1) == ',')
      *p2++ = '"';
  }
  *p2 = 0;

  /* show it works */
  printf("%s\n", r);
  return 0;
}

显示test,"blabla,"blabla,"blabla

---

如果您想在备注中也将\放在前面，

#include <stdio.h>
#include <stdlib.h>

int main()
{
  const char *mystring = "test,blabla,blabla,blabla";
  int n = 0;
  const char * p1;

  /* compute result length */
  for (p1 = mystring; *p1; ++p1)
    n += (*p1 == ',') ? 3 : 1;

  /* make result string */
  char * r = malloc(n + 1);
  char * p2 = r;

  for (p1 = mystring; *p1; ++p1) {
    if ((*p2++ = *p1) == ',') {
      p2[0] = '\\';
      p2[1] = '"';
      p2 += 2;
    }
  }
  *p2 = 0;

  /* show it works */
  printf("%s\n", r);
  return 0;
}

显示：test,\"blabla,\"blabla,\"blabla